1
|
Issotina Zibrila A, Zhou J, Wang X, Zeng M, Ali MA, Liu X, Alkuhali AA, Zeng Z, Meng Y, Wang Z, Li X, Liu J. Placental ischemia-upregulated angiotensin II type 1 receptor in hypothalamic paraventricular nucleus contributes to hypertension in rat. Pflugers Arch 2024:10.1007/s00424-024-03010-2. [PMID: 39215834 DOI: 10.1007/s00424-024-03010-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/30/2024] [Accepted: 08/12/2024] [Indexed: 09/04/2024]
Abstract
Preeclampsia (PE) is associated with increased angiotensin II sensitivity and poor neurological outcomes marked by temporal loss of neural control of blood pressure. Yet the role of centrally expressed angiotensin II type 1 receptor (AT1R) within the paraventricular nucleus of the hypothalamus (PVN) in the PE model is not understood. In a PE rat model with reduced placental perfusion pressure (RUPP) induced on gestational day 14 (GD14), the PVN expression and cellular localization of AT1R were assessed using immunofluorescence and western blotting. The sensitivity of RUPP to acute angiotensin II infusion was assessed. AT1R was antagonized by losartan (100 µg/kg/day) for 5 days intracerebroventricularly (ICV). Hemodynamic data and samples were collected on GD19 for further analysis. RUPP upregulated (p < 0.05) mRNA and protein of AT1R within the PVN and lowered (p < 0.05) circulating angiotensin II in rats. RUPP increased neural and microglial activation. Cellular localization assessment revealed that AT1R was primarily expressed in neurons and slightly in microglia and astrocytes. Infusion of 100 ng/kg as bolus increased the mean arterial pressure (MAP in mmHg) in both RUPP and Sham. ICV losartan infusion attenuated RUPP-increased MAP (113.6 ± 6.22 in RUPP vs. 92.16 ± 5.30 in RUPP + Los, p = 0.021) and the expression of nuclear transcription factor NF-κB, tyrosine hydroxylase (TH), NADPH oxidase 4 (NOX4) and reactive oxygen species (ROS) in the PVN. Our data suggest that centrally expressed AT1R, within the PVN, contributes to placental ischemia-induced hypertension in RUPP rats highlighting its therapeutic potential in PE.
Collapse
Affiliation(s)
- Abdoulaye Issotina Zibrila
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Jun Zhou
- Department of Pharmacology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, Xi'an, 710061, Shaanxi, P. R. China
| | - Xiaomin Wang
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Ming Zeng
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Md Ahasan Ali
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Xiaoxu Liu
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Asma A Alkuhali
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Zhaoshu Zeng
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Yuan Meng
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China
| | - Zheng Wang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, P. R. China
| | - Xuelan Li
- Department of Obstetrics & Gynecology, First Affiliated Hospital of Xi'an Jiaotong University, No. 277 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China.
| | - Jinjun Liu
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Key Laboratory of Environment and Genes Related to Diseases, No. 76 Yanta West Road, Xi'an, 710061, Shaanxi, P. R. China.
| |
Collapse
|
2
|
Colin M, Delaitre C, Foulquier S, Dupuis F. The AT 1/AT 2 Receptor Equilibrium Is a Cornerstone of the Regulation of the Renin Angiotensin System beyond the Cardiovascular System. Molecules 2023; 28:5481. [PMID: 37513355 PMCID: PMC10383525 DOI: 10.3390/molecules28145481] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/11/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
The AT1 receptor has mainly been associated with the pathological effects of the renin-angiotensin system (RAS) (e.g., hypertension, heart and kidney diseases), and constitutes a major therapeutic target. In contrast, the AT2 receptor is presented as the protective arm of this RAS, and its targeting via specific agonists is mainly used to counteract the effects of the AT1 receptor. The discovery of a local RAS has highlighted the importance of the balance between AT1/AT2 receptors at the tissue level. Disruption of this balance is suggested to be detrimental. The fine tuning of this balance is not limited to the regulation of the level of expression of these two receptors. Other mechanisms still largely unexplored, such as S-nitrosation of the AT1 receptor, homo- and heterodimerization, and the use of AT1 receptor-biased agonists, may significantly contribute to and/or interfere with the settings of this AT1/AT2 equilibrium. This review will detail, through several examples (the brain, wound healing, and the cellular cycle), the importance of the functional balance between AT1 and AT2 receptors, and how new molecular pharmacological approaches may act on its regulation to open up new therapeutic perspectives.
Collapse
Affiliation(s)
- Mélissa Colin
- CITHEFOR, Université de Lorraine, F-54000 Nancy, France
- Department of Pharmacology and Toxicology, MHeNS-School for Mental Health and Neuroscience, Maastricht University, 6200 MD Maastricht, The Netherlands
| | | | - Sébastien Foulquier
- Department of Pharmacology and Toxicology, MHeNS-School for Mental Health and Neuroscience, Maastricht University, 6200 MD Maastricht, The Netherlands
- CARIM-School for Cardiovascular Diseases, Maastricht University, 6200 MD Maastricht, The Netherlands
| | | |
Collapse
|
3
|
Jia XY, Jiang DL, Jia XT, Fu LY, Tian H, Liu KL, Qi J, Kang YM, Yu XJ. Capsaicin improves hypertension and cardiac hypertrophy via SIRT1/NF-κB/MAPKs pathway in the hypothalamic paraventricular nucleus. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2023; 118:154951. [PMID: 37453193 DOI: 10.1016/j.phymed.2023.154951] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 06/09/2023] [Accepted: 07/04/2023] [Indexed: 07/18/2023]
Abstract
BACKGROUND Hypertension has seriously affected a large part of the adult and elderly population. The complications caused by hypertension are important risk factors for cardiovascular disease accidents. Capsaicin, a pungent component of chili pepper has been revealed to improve hypertension. However, its potential mechanism in improving hypertension remains to be explored. PURPOSE In the present study, we aimed to investigate whether capsaicin could attenuate the SIRT1/NF-κB/MAPKs pathway in the paraventricular nucleus of hypothalamus (PVN). METHODS We used spontaneous hypertensive rats (SHRs) as animal model rats. Micro osmotic pump was used to give capsaicin through PVN for 28 days, starting from age12-week-old. RESULTS The results showed that capsaicin significantly reduced blood pressure from the 16th day of infusion onward. At the end of the experimental period, we measured cardiac hypertrophy index and the heart rate (HR), and the results showed that the cardiac hypertrophy and heart rate of rats was significantly improved upon capsaicin chronic infusion. Norepinephrine (NE) and epinephrine (EPI) in plasma of SHRs treated with capsaicin were also decreased. Additionally, capsaicin increased the protein expression and number of positive cells of SIRT1 and the 67-kDa isoform of glutamate decarboxylase (GAD67), decreased the production of reactive oxygen species (ROS), number of positive cells of NOX2, those of Angiotensin Converting Enzyme (ACE) and p-IKKβ, tyrosine hydroxylase (TH), the gene expression levels of NOX4 and pro-inflammatory cytokines. Capsaicin also decreased the relative protein expressions of protein in MAPKs pathway. CONCLUSION Current data indicated that capsaicin within the PVN improves hypertension and cardiac hypertrophy via SIRT1/NF-κB/MAPKs pathway in the PVN of SHRs, supporting its potential as candidate drug for preventing and improving hypertension.
Collapse
Affiliation(s)
- Xiu-Yue Jia
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China; Department of Physiology, Basic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, China
| | - Da-Li Jiang
- Department of Urology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Xiao-Tao Jia
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China
| | - Li-Yan Fu
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China
| | - Hua Tian
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China
| | - Kai-Li Liu
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China
| | - Jie Qi
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China
| | - Yu-Ming Kang
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China
| | - Xiao-Jing Yu
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Basic Medical Sciences, Shaanxi Engineering and Research Center of Vaccine, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry of China, Xi'an 710061, China.
| |
Collapse
|
4
|
Fan JF, Wang W, Tan X, Ye P, Li JK, Niu LY, Li WY, Wang WZ, Wang YK. Contribution of cyclooxygenase-2 overexpression to enhancement in tonically active glutamatergic inputs to the rostral ventrolateral medulla in hypertension. J Hypertens 2022; 40:2394-2405. [PMID: 36189462 DOI: 10.1097/hjh.0000000000003268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
OBJECTIVE Cyclooxygenase (COX) is critical in regulating cardiovascular function, but its role involved in the central control of blood pressure (BP) is uncovered. The tonic glutamatergic inputs to the rostral ventrolateral medulla (RVLM) are enhanced in hypertension. Here, the present study was designed to investigate the effect and mechanism of central COX on tonic glutamatergic inputs to the RVLM and BP regulation. METHODS Wistar-Kyoto (WKY) rats and spontaneous hypertensive rats (SHRs) received RVLM microinjection of adeno-associated viral vectors to promote or inhibit the COX2 expression were subjected to subsequent experiments. Glutamate level and glutaminase expression were detected by ELISA and western blot, respectively. The function of tonic glutamatergic inputs was assessed by BP response to microinjection of the glutamate receptor antagonist into the RVLM. PC12 cells were used to detect the underlying signal pathway. RESULTS The RVLM COX2 expression and prostaglandin E2 level were significant higher in SHRs than in WKY rats. Overexpression of COX2 in the RVLM produced an increase in basal BP, RVLM glutamate level, and glutaminase expression in WKY rats, while they were significantly reduced by interfering with COX2 expression in SHRs. Microinjections of the glutamate receptor antagonist into the RVLM produced a significant BP decrease in WKY rats with COX2 overexpression pretreatment. Furthermore, the increased levels of BP, glutamate content, and glutaminase activity in the RVLM evoked by central infusion of angiotensin II were attenuated in COX2 knockout mice. It was also found that prostaglandin E2 increased supernatant glutamate level and phosphorylation of signal transducer and activator of transcription 3 in PC12 cells. CONCLUSION Our findings suggest that upregulated COX2 expression enhances the tonically active glutamatergic inputs to the RVLM, which is associated with cardiovascular regulation in hypertension.
Collapse
Affiliation(s)
- Jie-Fu Fan
- Department of Marine Biomedicine and Polar Medicine, Naval Medical University (Second Military Medical University), Shanghai, China
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Renal Denervation Influences Angiotensin II Types 1 and 2 Receptors. Int J Nephrol 2022; 2022:8731357. [PMID: 36262553 PMCID: PMC9576444 DOI: 10.1155/2022/8731357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 09/05/2022] [Accepted: 09/12/2022] [Indexed: 11/17/2022] Open
Abstract
The sympathetic and renin-angiotensin systems (RAS) are two critical regulatory systems in the kidney which affect renal hemodynamics and function. These two systems interact with each other so that angiotensin II (Ang II) has the presynaptic effect on the norepinephrine secretion. Another aspect of this interaction is that the sympathetic nervous system affects the function and expression of local RAS receptors, mainly Ang II receptors. Therefore, in many pathological conditions associated with an increased renal sympathetic tone, these receptors' expression changes and renal denervation can normalize these changes and improve the diseases. It seems that the renal sympathectomy can alter Ang II receptors expression and the distribution of RAS receptors in the kidneys, which influence renal functions.
Collapse
|
6
|
Renin-a in the Subfornical Organ Plays a Critical Role in the Maintenance of Salt-Sensitive Hypertension. Biomolecules 2022; 12:biom12091169. [PMID: 36139008 PMCID: PMC9496084 DOI: 10.3390/biom12091169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/20/2022] [Accepted: 08/22/2022] [Indexed: 11/17/2022] Open
Abstract
The brain renin-angiotensin system plays important roles in blood pressure and cardiovascular regulation. There are two isoforms of prorenin in the brain: the classic secreted form (prorenin/sREN) encoded by renin-a, and an intracellular form (icREN) encoded by renin-b. Emerging evidence indicates the importance of renin-b in cardiovascular and metabolic regulation. However, the role of endogenous brain prorenin in the development of salt-sensitive hypertension remains undefined. In this study, we test the hypothesis that renin-a produced locally in the brain contributes to the pathogenesis of hypertension. Using RNAscope, we report for the first time that renin mRNA is expressed in several regions of the brain, including the subfornical organ (SFO), the paraventricular nucleus of the hypothalamus (PVN), and the brainstem, where it is found in glutamatergic, GABAergic, cholinergic, and tyrosine hydroxylase-positive neurons. Notably, we found that renin mRNA was significantly elevated in the SFO and PVN in a mouse model of DOCA-salt–induced hypertension. To examine the functional importance of renin-a in the SFO, we selectively ablated renin-a in the SFO in renin-a–floxed mice using a Cre-lox strategy. Importantly, renin-a ablation in the SFO attenuated the maintenance of DOCA-salt–induced hypertension and improved autonomic function without affecting fluid or sodium intake. Molecularly, ablation of renin-a prevented the DOCA-salt–induced elevation in NADPH oxidase 2 (NOX2) in the SFO without affecting NOX4 or angiotensin II type 1 and 2 receptors. Collectively, our findings demonstrate that endogenous renin-a within the SFO is important for the pathogenesis of salt-sensitive hypertension.
Collapse
|
7
|
Li Y, Ricardo SD, Samuel CS. Enhancing the Therapeutic Potential of Mesenchymal Stromal Cell-Based Therapies with an Anti-Fibrotic Agent for the Treatment of Chronic Kidney Disease. Int J Mol Sci 2022; 23:ijms23116035. [PMID: 35682717 PMCID: PMC9181689 DOI: 10.3390/ijms23116035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/24/2022] [Accepted: 05/26/2022] [Indexed: 01/02/2023] Open
Abstract
Chronic kidney disease (CKD) affects 1 in 10 members of the general population, placing these patients at an increasingly high risk of kidney failure. Despite the significant burden of CKD on various healthcare systems, there are no effective cures that reverse or even halt its progression. In recent years, human bone-marrow-derived mesenchymal stromal cells (BM-MSCs) have been recognised as a novel therapy for CKDs, owing to their well-established immunomodulatory and tissue-reparative properties in preclinical settings, and their promising safety profile that has been demonstrated in patients with CKDs from several clinical trials. However, renal fibrosis (scarring), a hallmark of CKD, has been shown to impair the viability and functionality of BM-MSCs post-transplantation. This has suggested that BM-MSCs might require a pre-treatment or adjunct therapy that can enhance the viability and therapeutic efficacy of these stromal cells in chronic disease settings. To address this, recent studies that have combined BM-MSCs with the anti-fibrotic drug serelaxin (RLX), have demonstrated the enhanced therapeutic potential of this combination therapy in normotensive and hypertensive preclinical models of CKD. In this review, a critical appraisal of the preclinical data available on the anti-fibrotic and renoprotective actions of BM-MSCs or RLX alone and when combined, as a treatment option for normotensive vs. hypertensive CKD, is discussed.
Collapse
Affiliation(s)
- Yifang Li
- Cardiovascular Disease Program, Department of Pharmacology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia;
| | - Sharon D. Ricardo
- Development and Stem Cells Program, Department of Pharmacology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
- Correspondence: (S.D.R.); (C.S.S.)
| | - Chrishan S. Samuel
- Cardiovascular Disease Program, Department of Pharmacology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia;
- Development and Stem Cells Program, Department of Pharmacology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, VIC 3010, Australia
- Correspondence: (S.D.R.); (C.S.S.)
| |
Collapse
|
8
|
Lucera GM, Menani JV, Colombari E, Colombari DSA. ANG II and Aldosterone Acting Centrally Participate in the Enhanced Sodium Intake in Water-Deprived Renovascular Hypertensive Rats. Front Pharmacol 2021; 12:679985. [PMID: 34113255 PMCID: PMC8186501 DOI: 10.3389/fphar.2021.679985] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/04/2021] [Indexed: 11/29/2022] Open
Abstract
Renovascular hypertension is a type of secondary hypertension caused by renal artery stenosis, leading to an increase in the renin–angiotensin–aldosterone system (RAAS). Two-kidney, 1-clip (2K1C) is a model of renovascular hypertension in which rats have an increased sodium intake induced by water deprivation (WD), a common situation found in the nature. In addition, a high-sodium diet in 2K1C rats induces glomerular lesion. Therefore, the purpose of this study was to investigate whether angiotensin II (ANG II) and/or aldosterone participates in the increased sodium intake in 2K1C rats under WD. In addition, we also verified if central AT1 and mineralocorticoid receptor blockade would change the high levels of arterial pressure in water-replete (WR) and WD 2K1C rats, because blood pressure changes can facilitate or inhibit water and sodium intake. Finally, possible central areas activated during WD or WD followed by partial rehydration (PR) in 2K1C rats were also investigated. Male Holtzman rats (150–180 g) received a silver clip around the left renal artery to induce renovascular hypertension. Six weeks after renal surgery, a stainless-steel cannula was implanted in the lateral ventricle, followed by 5–7 days of recovery before starting tests. Losartan (AT1 receptor antagonist) injected intracerebroventricularly attenuated water intake during the thirst test. Either icv losartan or RU28318 (mineralocorticoid receptor antagonist) reduced 0.3 M NaCl intake, whereas the combination of losartan and RU28318 icv totally blocked 0.3 M NaCl intake induced by WD in 2K1C rats. Losartan and RU28318 icv did not change hypertension levels of normohydrated 2K1C rats, but reduced the increase in mean arterial pressure (MAP) produced by WD. c-Fos expression increased in the lamina terminalis and in the NTS in WD condition, and increased even more after WD-PR. These results suggest the participation of ANG II and aldosterone acting centrally in the enhanced sodium intake in WD 2K1C rats, and not in the maintenance of hypertension in satiated and fluid-replete 2K1C rats.
Collapse
Affiliation(s)
- Gabriela Maria Lucera
- Department of Physiology and Pathology, School of Dentistry, Sao Paulo State University, Araraquara, Brazil
| | - José Vanderlei Menani
- Department of Physiology and Pathology, School of Dentistry, Sao Paulo State University, Araraquara, Brazil
| | - Eduardo Colombari
- Department of Physiology and Pathology, School of Dentistry, Sao Paulo State University, Araraquara, Brazil
| | | |
Collapse
|
9
|
Su C, Xue J, Ye C, Chen A. Role of the central renin‑angiotensin system in hypertension (Review). Int J Mol Med 2021; 47:95. [PMID: 33846799 PMCID: PMC8041481 DOI: 10.3892/ijmm.2021.4928] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 01/25/2021] [Indexed: 12/16/2022] Open
Abstract
Present in more than one billion adults, hypertension is the most significant modifiable risk factor for mortality resulting from cardiovascular disease. Although its pathogenesis is not yet fully understood, the disruption of the renin-angiotensin system (RAS), consisting of the systemic and brain RAS, has been recognized as one of the primary reasons for several types of hypertension. Therefore, acquiring sound knowledge of the basic science of RAS and the under- lying mechanisms of the signaling pathways associated with RAS may facilitate the discovery of novel therapeutic targets with which to promote the management of patients with cardiovascular and kidney disease. In total, 4 types of angiotensin II receptors have been identified (AT1R-AT4R), of which AT1R plays the most important role in vasoconstriction and has been most extensively studied. It has been found in several regions of the brain, and its distribution is highly associated with that of angiotensin-like immunoreactivity in nerve terminals. The effect of AT1R involves the activation of multiple media and signaling pathways, among which the most important signaling pathways are considered to be AT1R/JAK/STAT and Ras/Raf/MAPK pathways. In addition, the regulation of the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and cyclic AMP response element-binding (CREB) pathways is also closely related to the effect of ATR1. Their mechanisms of action are related to pro-inflammatory and sympathetic excitatory effects. Central AT1R is involved in almost all types of hypertension, including spontaneous hypertension, salt-sensitive hypertension, obesity-induced hypertension, renovascular hypertension, diabetic hypertension, L-NAME-induced hypertension, stress-induced hypertension, angiotensin II-induced hyper- tension and aldosterone-induced hypertension. There are 2 types of central AT1R blockade, acute blockade and chronic blockade. The latter can be achieved by chemical blockade or genetic engineering. The present review article aimed to high- light the prevalence, functions, interactions and modulation means of central AT-1R in an effort to assist in the treatment of several pathological conditions. The identification of angiotensin-derived peptides and the development of AT-2R agonists may provide a wider perspective on RAS, as well as novel therapeutic strategies.
Collapse
Affiliation(s)
- Chuanxin Su
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center of Translational Medicine for Cardiovascular Disease, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu 211166, P.R. China
| | - Jinhua Xue
- Research Center for Cardiovascular and Cerebrovascular Diseases, The University of Duisburg‑Essen, Duisburg‑Essen University, D-45122 Essen, Germany
| | - Chao Ye
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center of Translational Medicine for Cardiovascular Disease, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu 211166, P.R. China
| | - Aidong Chen
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center of Translational Medicine for Cardiovascular Disease, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu 211166, P.R. China
| |
Collapse
|
10
|
Fernandes MV, Rosso Melo M, Mowry FE, Lucera GM, Lauar MR, Frigieri G, Biancardi VC, Menani JV, Colombari DSA, Colombari E. Intracranial Pressure During the Development of Renovascular Hypertension. Hypertension 2021; 77:1311-1322. [PMID: 33689460 DOI: 10.1161/hypertensionaha.120.16217] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
[Figure: see text].
Collapse
Affiliation(s)
- Marcos Vinicius Fernandes
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| | - Mariana Rosso Melo
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| | - Francesca Elisabeth Mowry
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine (F.E.M., V.C.B.), Auburn University, AL.,Center for Neurosciences Research Initiative (F.E.M., V.C.B.), Auburn University, AL
| | - Gabriela Maria Lucera
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| | - Mariana Ruiz Lauar
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| | - Gustavo Frigieri
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| | - Vinicia Campana Biancardi
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine (F.E.M., V.C.B.), Auburn University, AL.,Center for Neurosciences Research Initiative (F.E.M., V.C.B.), Auburn University, AL
| | - Jose V Menani
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| | - Débora Simões Almeida Colombari
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| | - Eduardo Colombari
- From the Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, Araraquara, Brazil (M.V.F.S., M.R.M., G.M.L., M.R.L., G.F., J.V.M., D.S.A.C., E.C.)
| |
Collapse
|
11
|
de Ataides Raquel H, Souza Guazelli CF, Verri WA, Michelini LC, Martins-Pinge MC. Swimming training reduces iNOS expression, augments the antioxidant defense and reduces sympathetic responsiveness in the rostral ventrolateral medulla of normotensive male rats. Brain Res Bull 2021; 170:225-233. [PMID: 33631270 DOI: 10.1016/j.brainresbull.2021.02.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/17/2021] [Accepted: 02/21/2021] [Indexed: 11/30/2022]
Abstract
We sought to investigate whether RVLM iNOS activity and oxidative profile may participate in the reduction of sympathetic responsiveness in swimming trained normotensive rats. Sedentary (S) and swimming trained (T) Wistar male rats chronically instrumented with an arterial catheter and guide cannula into the RVLM were submitted to continuous pressure and heart rate (HR) recordings and determination of autonomic control (power spectral analysis) before and after unilateral RVLM iNOS inhibition (aminoguanidine, 250 pmol/100 nL). Other S and T rats received local l-glutamate microinjection (5 nmol/100 nL). In separate S and T groups not submitted to brainstem cannulation, fresh bilateral RVLM punchs were collected for iNOS gene expression (qPCR); reduced glutathione and lipid peroxidation quantification (spectrophotometry); iron-reducing antioxidant (FRAP) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS˙+) scavenger assays. iNOS gene expression was confirmed in fixed RVLM slices (immunofluorescence). T rats exhibited resting bradycardia, lower sympathovagal balance, reduced RVLM iNOS gene/protein expression and higher antioxidant capacity. Decreased iNOS expression was positively correlated with reduced HR. Pressor and tachycardic response to l-Glutamate were smaller in T rats. Aminoguanidine microinjection reduced sympathetic activity in S rats but did not change it in T rats expressing reduced RVLM iNOS content. Our data indicate that iNOS, expressed in the RVLM of normotensive male rats, has tonic effects on sympathetic activity and that swimming training is an efficient tool to reduce iNOS expression and augment the antioxidant defense, thus reducing glutamatergic responsiveness and sympathetic drive to cardiovascular effectors.
Collapse
Affiliation(s)
- Hiviny de Ataides Raquel
- Departament of Physiological Sciences, Center of Biological Sciences, State University of Londrina, Londrina, PR, Brazil; Departament of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Carla Fabiana Souza Guazelli
- Departament of Pathological Sciences, Center of Biological Sciences, State University of Londrina, Londrina, PR, Brazil
| | - Waldiceu A Verri
- Departament of Pathological Sciences, Center of Biological Sciences, State University of Londrina, Londrina, PR, Brazil
| | - Lisete C Michelini
- Departament of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Marli Cardoso Martins-Pinge
- Departament of Physiological Sciences, Center of Biological Sciences, State University of Londrina, Londrina, PR, Brazil.
| |
Collapse
|
12
|
Milanez MIO, Veiga AC, Martins BS, Pontes RB, Bergamaschi CT, Campos RR, Nishi EE. Renal Sensory Activity Regulates the γ-Aminobutyric Acidergic Inputs to the Paraventricular Nucleus of the Hypothalamus in Goldblatt Hypertension. Front Physiol 2020; 11:601237. [PMID: 33384613 PMCID: PMC7769809 DOI: 10.3389/fphys.2020.601237] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/27/2020] [Indexed: 12/27/2022] Open
Abstract
Renal sensory activity is centrally integrated within brain nuclei involved in the control of cardiovascular function, suggesting that renal afferents regulate basal and reflex sympathetic vasomotor activity. Evidence has shown that renal deafferentation (DAx) evokes a hypotensive and sympathoinhibitory effect in experimental models of cardiovascular diseases; however, the underlying mechanisms involved in this phenomenon need to be clarified, especially those related to central aspects. We aimed to investigate the role of renal afferents in the control of γ-aminobutyric acid (GABA)ergic inputs to the paraventricular nucleus (PVN) of the hypothalamus in renovascular hypertensive (2K1C) rats and their influence in the regulation of cardiovascular function. Hypertension was induced by clipping the left renal artery. After 4 weeks, renal DAx was performed by exposing the left renal nerve to a 33 mM capsaicin solution for 15 min. After 2 weeks of DAx, microinjection of muscimol into the PVN was performed in order to evaluate the influence of GABAergic activity in the PVN and its contribution to the control of renal sympathetic nerve activity (rSNA) and blood pressure (BP). Muscimol microinjected into the PVN triggered a higher drop in BP and rSNA in the 2K1C rats and renal DAx mitigated these responses. These results suggest that renal afferents are involved in the GABAergic changes found in the PVN of 2K1C rats. Although the functional significance of this phenomenon needs to be clarified, it is reasonable to speculate that GABAergic alterations occur to mitigate microglia activation-induced sympathoexcitation in the PVN of 2K1C rats.
Collapse
Affiliation(s)
- Maycon I O Milanez
- Department of Physiology, Cardiovascular Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Amanda C Veiga
- Department of Physiology, Cardiovascular Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Beatriz S Martins
- Department of Physiology, Cardiovascular Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Roberto B Pontes
- Department of Physiology, Cardiovascular Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Cassia T Bergamaschi
- Department of Physiology, Cardiovascular Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ruy R Campos
- Department of Physiology, Cardiovascular Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Erika E Nishi
- Department of Physiology, Cardiovascular Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| |
Collapse
|
13
|
Thymoquinone Upregulates Catalase Gene Expression and Preserves the Structure of the Renal Cortex of Propylthiouracil-Induced Hypothyroid Rats. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:3295831. [PMID: 32774669 PMCID: PMC7391089 DOI: 10.1155/2020/3295831] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/31/2020] [Accepted: 06/08/2020] [Indexed: 01/06/2023]
Abstract
Background The association between hypothyroidism and renal diseases has been described in many studies. Nigella Sativa was among the recently reported natural product that has the potential to prevent renal tissue damage and fibrosis. The aim of this study was to evaluate the possible protective effect of thymoquinone on the structure of the renal cortex of hypothyroid rats and explore the mechanism behind it. Methods An experimental model of hypothyroidism was induced in adult male Wistar rats by administration of propylthiouracil (6 mg/kg/body weight). One hypothyroid group was treated with thymoquinone at the dose of 50 mg/kg/body weight and compared to the untreated group. Thyroid function and oxidant/antioxidant status were assessed in the serum. Catalase gene expression was assessed using the real-time polymerase chain reaction. The kidney was assessed both histologically and immunohistochemically. Results Administration of propylthiouracil resulted in a significant decrease in the serum levels of nitric oxide, reduced glutathione, and superoxide dismutase activity while the level of malondialdehyde significantly (p < 0.001) increased. Administration of thymoquinone alleviated this effect on the thyroid hormones and significantly increased the serum levels of antioxidants. Thymoquinone significantly (p < 0.001) upregulated catalase transcription by about 24-fold and could block the hypothyroidism-induced glomerular and tubular injury. Conclusion Thymoquinone may have a potential protective effect against hypothyroidism-induced renal injury acting through the attenuation of the oxidative stress and upregulation of renal catalase gene expression.
Collapse
|
14
|
Elsaafien K, de Kloet AD, Krause EG, Sumners C. Brain Angiotensin Type-1 and Type-2 Receptors in Physiological and Hypertensive Conditions: Focus on Neuroinflammation. Curr Hypertens Rep 2020; 22:48. [PMID: 32661792 PMCID: PMC7780348 DOI: 10.1007/s11906-020-01062-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
PURPOSE OF REVIEW To review recent data that suggest opposing effects of brain angiotensin type-1 (AT1R) and type-2 (AT2R) receptors on blood pressure (BP). Here, we discuss recent studies that suggest pro-hypertensive and pro-inflammatory actions of AT1R and anti-hypertensive and anti-inflammatory actions of AT2R. Further, we propose mechanisms for the interplay between brain angiotensin receptors and neuroinflammation in hypertension. RECENT FINDINGS The renin-angiotensin system (RAS) plays an important role in regulating cardiovascular physiology. This includes brain AT1R and AT2R, both of which are expressed in or adjacent to brain regions that control BP. Activation of AT1R within those brain regions mediate increases in BP and cause neuroinflammation, which augments the BP increase in hypertension. The fact that AT1R and AT2R have opposing actions on BP suggests that AT1R and AT2R may have similar opposing actions on neuroinflammation. However, the mechanisms by which brain AT1R and AT2R mediate neuroinflammatory responses remain unclear. The interplay between brain angiotensin receptor subtypes and neuroinflammation exacerbates or protects against hypertension.
Collapse
Affiliation(s)
- Khalid Elsaafien
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, FL, USA
| | - Annette D de Kloet
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, USA
- Center for Integrative Cardiovascular and Metabolic Diseases, University of Florida, Gainesville, FL, USA
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Eric G Krause
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, FL, USA
- Center for Integrative Cardiovascular and Metabolic Diseases, University of Florida, Gainesville, FL, USA
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Colin Sumners
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, USA.
- Center for Integrative Cardiovascular and Metabolic Diseases, University of Florida, Gainesville, FL, USA.
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
| |
Collapse
|
15
|
Brouillard C, Carrive P, Camus F, Bénoliel JJ, Sévoz-Couche C. Vulnerability to stress consequences induced by repeated social defeat in rats: Contribution of the angiotensin II type 1 receptor in cardiovascular alterations associated to low brain derived neurotrophic factor. Eur J Pharmacol 2019; 861:172595. [DOI: 10.1016/j.ejphar.2019.172595] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 08/02/2019] [Accepted: 08/07/2019] [Indexed: 01/17/2023]
|
16
|
Nishi EE, Almeida VR, Amaral FG, Simon KA, Futuro-Neto HA, Pontes RB, Cespedes JG, Campos RR, Bergamaschi CT. Melatonin attenuates renal sympathetic overactivity and reactive oxygen species in the brain in neurogenic hypertension. Hypertens Res 2019; 42:1683-1691. [PMID: 31316170 DOI: 10.1038/s41440-019-0301-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 06/20/2019] [Accepted: 06/26/2019] [Indexed: 01/26/2023]
Abstract
Sympathetic overactivation contributes to the pathogenesis of both experimental and human hypertension. We have previously reported that oxidative stress in sympathetic premotor neurons leads to arterial baroreflex dysfunction and increased sympathetic drive to the kidneys in an experimental model of neurogenic hypertension. In this study, we hypothesized that melatonin, a potent antioxidant, may be protective in the brainstem regions involved in the tonic and reflex control of blood pressure (BP) in renovascular hypertensive rats. Neurogenic hypertension was induced by placing a silver clip (gap of 0.2 mm) around the left renal artery, and after 5 weeks of renal clip placement, the rats were treated orally with melatonin (30 mg/kg/day) by gavage for 15 days. At the end of melatonin treatment, we evaluated baseline mean arterial pressure (MAP), renal sympathetic nerve activity (rSNA), and the baroreflex control of heart rate (HR) and rSNA. Reactive oxygen species (ROS) were detected within the brainstem regions by dihydroethidium staining. Melatonin treatment effectively reduced baseline MAP and sympathoexcitation to the ischemic kidney in renovascular hypertensive rats. The baroreflex control of HR and rSNA were improved after melatonin treatment in the hypertensive group. Moreover, there was a preferential decrease in ROS within the rostral ventrolateral medulla (RVLM) and the nucleus of the solitary tract (NTS). Therefore, our study indicates that melatonin is effective in reducing renal sympathetic overactivity associated with decreased ROS in brainstem regions that regulate BP in an experimental model of neurogenic hypertension.
Collapse
Affiliation(s)
- Erika E Nishi
- Department of Physiology, Campus São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Vitor R Almeida
- Department of Physiology, Campus São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Fernanda G Amaral
- Department of Physiology, Campus São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Karin A Simon
- Department of Biological Sciences, Campus Diadema, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | - Roberto B Pontes
- Department of Physiology, Campus São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Juliana G Cespedes
- Institute of Science and Technology, Campus São José dos Campos, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ruy R Campos
- Department of Physiology, Campus São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Cássia T Bergamaschi
- Department of Physiology, Campus São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.
| |
Collapse
|
17
|
Chan JYH, Chan SHH. Differential impacts of brain stem oxidative stress and nitrosative stress on sympathetic vasomotor tone. Pharmacol Ther 2019; 201:120-136. [PMID: 31153955 DOI: 10.1016/j.pharmthera.2019.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 05/24/2019] [Indexed: 02/07/2023]
Abstract
Based on work-done in the rostral ventrolateral medulla (RVLM), this review presents four lessons learnt from studying the differential impacts of oxidative stress and nitrosative stress on sympathetic vasomotor tone and their clinical and therapeutic implications. The first lesson is that an increase in sympathetic vasomotor tone because of augmented oxidative stress in the RVLM is responsible for the generation of neurogenic hypertension. On the other hand, a shift from oxidative stress to nitrosative stress in the RVLM underpins the succession of increase to decrease in sympathetic vasomotor tone during the progression towards brain stem death. The second lesson is that, by having different cellular sources, regulatory mechanisms on synthesis and degradation, kinetics of chemical reactions, and downstream signaling pathways, reactive oxygen species and reactive nitrogen species should not be regarded as a singular moiety. The third lesson is that well-defined differential roles of oxidative stress and nitrosative stress with distinct regulatory mechanisms in the RVLM during neurogenic hypertension and brain stem death clearly denote that they are not interchangeable phenomena with unified cellular actions. Special attention must be paid to their beneficial or detrimental roles under a specific disease or a particular time-window of that disease. The fourth lesson is that, to be successful, future antioxidant therapies against neurogenic hypertension must take into consideration the much more complicated picture than that presented in this review on the generation, maintenance, regulation or modulation of the sympathetic vasomotor tone. The identification that the progression towards brain stem death entails a shift from oxidative stress to nitrosative stress in the RVLM may open a new vista for therapeutic intervention to slow down this transition.
Collapse
Affiliation(s)
- Julie Y H Chan
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
| | - Samuel H H Chan
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China.
| |
Collapse
|
18
|
Menegatti R, Carvalho FS, Lião LM, Villavicencio B, Verli H, Mourão AA, Xavier CH, Castro CH, Pedrino GR, Franco OL, Oliveira-Silva I, Ashpole NM, Silva ON, Costa EA, Fajemiroye JO. Novel choline analog 2-(4-((1-phenyl-1H-pyrazol-4-yl)methyl)piperazin-1-yl)ethan-1-ol produces sympathoinhibition, hypotension, and antihypertensive effects. Naunyn Schmiedebergs Arch Pharmacol 2019; 392:1071-1083. [DOI: 10.1007/s00210-019-01649-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 03/29/2019] [Indexed: 12/14/2022]
|
19
|
Guimarães DD, Cruz JC, Carvalho-Galvão A, Zhuge Z, Marques SM, Naves LM, Persson AEG, Weitzberg E, Lundberg JO, Balarini CM, Pedrino GR, Braga VA, Carlström M. Dietary Nitrate Reduces Blood Pressure in Rats With Angiotensin II–Induced Hypertension via Mechanisms That Involve Reduction of Sympathetic Hyperactivity. Hypertension 2019; 73:839-848. [DOI: 10.1161/hypertensionaha.118.12425] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Drielle D. Guimarães
- From the Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (D.D.G., J.C.C., Z.Z., A.E.G.P., E.W., J.O.L., M.C.)
- Biotechnology Center (D.D.G., J.C.C., A.C.-G., C.M.B., V.A.B.), Federal University of Paraiba, Joao Pessoa, Brazil
| | - Josiane C. Cruz
- From the Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (D.D.G., J.C.C., Z.Z., A.E.G.P., E.W., J.O.L., M.C.)
- Biotechnology Center (D.D.G., J.C.C., A.C.-G., C.M.B., V.A.B.), Federal University of Paraiba, Joao Pessoa, Brazil
| | - Alynne Carvalho-Galvão
- Biotechnology Center (D.D.G., J.C.C., A.C.-G., C.M.B., V.A.B.), Federal University of Paraiba, Joao Pessoa, Brazil
| | - Zhengbing Zhuge
- From the Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (D.D.G., J.C.C., Z.Z., A.E.G.P., E.W., J.O.L., M.C.)
| | - Stefanne M. Marques
- Department of Physiological Sciences, Federal University of Goias, Goiania, Brazil (S.M.M., L.M.N., G.R.P.)
| | - Lara M. Naves
- Department of Physiological Sciences, Federal University of Goias, Goiania, Brazil (S.M.M., L.M.N., G.R.P.)
| | - A. Erik G. Persson
- From the Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (D.D.G., J.C.C., Z.Z., A.E.G.P., E.W., J.O.L., M.C.)
- Department of Medical Cell Biology, Uppsala University, Sweden (A.E.G.P.)
| | - Eddie Weitzberg
- From the Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (D.D.G., J.C.C., Z.Z., A.E.G.P., E.W., J.O.L., M.C.)
| | - Jon O. Lundberg
- From the Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (D.D.G., J.C.C., Z.Z., A.E.G.P., E.W., J.O.L., M.C.)
| | - Camille M. Balarini
- Biotechnology Center (D.D.G., J.C.C., A.C.-G., C.M.B., V.A.B.), Federal University of Paraiba, Joao Pessoa, Brazil
- Health Sciences Center (C.M.B.), Federal University of Paraiba, Joao Pessoa, Brazil
| | - Gustavo R. Pedrino
- Department of Physiological Sciences, Federal University of Goias, Goiania, Brazil (S.M.M., L.M.N., G.R.P.)
| | - Valdir A. Braga
- Biotechnology Center (D.D.G., J.C.C., A.C.-G., C.M.B., V.A.B.), Federal University of Paraiba, Joao Pessoa, Brazil
| | - Mattias Carlström
- From the Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (D.D.G., J.C.C., Z.Z., A.E.G.P., E.W., J.O.L., M.C.)
| |
Collapse
|
20
|
Importance of the commissural nucleus of the solitary tract in renovascular hypertension. Hypertens Res 2019; 42:587-597. [PMID: 30622315 DOI: 10.1038/s41440-018-0190-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 10/05/2018] [Accepted: 10/09/2018] [Indexed: 12/12/2022]
Abstract
The rodent renovascular hypertension model has been used to investigate the mechanisms promoting hypertension. The importance of the carotid body for renovascular hypertension has been demonstrated. As the commissural NTS (cNTS) is the first synaptic site in the central nervous system that receives information from carotid body chemoreceptors, we evaluated the contribution of cNTS to renovascular hypertension in the present study. Normotensive male Holtzman rats were implanted with a silver clip around the left renal artery to induce two-kidney, one-clip (2K1C) hypertension. Six weeks later, isoguvacine (a GABAA agonist) or losartan (an AT1 antagonist) was injected into the cNTS, and the effects were compared with carotid body removal. Immunohistochemistry for Iba-1 and GFAP to label microglia and astrocytes, respectively, and RT-PCR for components of the renin-angiotensin system and cytokines in the NTS were also performed 6 weeks after renal surgery. The inhibition of cNTS with isoguvacine or the blockade of AT1 receptors with losartan in the cNTS decreased the blood pressure and heart rate of 2K1C rats even more than carotid body removal did. The mRNA expression of NOX2, TNF-α and IL-6, microglia, and astrocytes also increased in the cNTS of 2K1C rats compared to that of normotensive rats. These results indicate that tonically active neurons within the cNTS are essential for the maintenance of hypertension in 2K1C rats. In addition to signals from the carotid body, the present results suggest that angiotensin II directly activates the cNTS and may also induce microgliosis and astrogliosis within the NTS, which, in turn, cause oxidative stress and neuroinflammation.
Collapse
|
21
|
|
22
|
Nishi EE, Lopes NR, Gomes GN, Perry JC, Sato AYS, Naffah-Mazzacoratti MG, Bergamaschi CT, Campos RR. Renal denervation reduces sympathetic overactivation, brain oxidative stress, and renal injury in rats with renovascular hypertension independent of its effects on reducing blood pressure. Hypertens Res 2018; 42:628-640. [PMID: 30573809 DOI: 10.1038/s41440-018-0171-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 10/19/2018] [Accepted: 10/31/2018] [Indexed: 12/27/2022]
Abstract
The underlying mechanisms by which renal denervation (RD) decreases blood pressure (BP) remain incompletely understood. In this study, we investigated the effects of ischemic kidney denervation on different sympathetic outflows, brain and renal expression of angiotensin-II receptors, oxidative stress and renal function markers in the 2-kidney, 1-clip (2K-1C) rat model. Surgical RD was performed in Wistar male rats 4-5 weeks after clip implantation. After 10 days of RD, BP, and the activity of sympathetic nerves projecting to the contralateral kidney (rSNA) and splanchnic region were partially reduced in 2K-1C rats, with no change in systemic renin-angiotensin system (RAS). To distinguish the effects of RD from the reduction in BP, 2K-1C rats were treated with hydralazine by oral gavage (25 mg/kg/day for 1 week). RD, but not hydralazine, normalized oxidative stress in the sympathetic premotor brain regions and improved intrarenal RAS, renal injury, and proteinuria. Furthermore, different mechanisms led to renal injury and oxidative stress in the ischemic and contralateral kidneys of 2K-1C rats. Injury and oxidative stress in the ischemic kidney were driven by the renal nerves. Although RD attenuated rSNA, injury and oxidative stress persisted in the contralateral kidney, probably due to increased BP. Therefore, nerves from the ischemic kidney at least partially contribute to the increase in BP, sympathetic outflows, brain oxidative stress, and renal alterations in rats with renovascular hypertension. Based on these findings, the reduction in oxidative stress in the brain is a central mechanism that contributes to the effects of RD on Goldblatt hypertension.
Collapse
Affiliation(s)
- Erika E Nishi
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.
| | - Nathalia R Lopes
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Guiomar N Gomes
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Juliana C Perry
- Department of Psychobiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Alex Y S Sato
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Maria G Naffah-Mazzacoratti
- Department of Neurology and Neurosurgery, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Cássia T Bergamaschi
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ruy R Campos
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| |
Collapse
|
23
|
Mourão AA, de Mello ABS, Dos Santos Moreira MC, Rodrigues KL, Lopes PR, Xavier CH, Gomes RM, Freiria-Oliveira AH, Blanch GT, Colombari E, Pedrino GR. Median preoptic nucleus excitatory neurotransmitters in the maintenance of hypertensive state. Brain Res Bull 2018; 142:207-215. [PMID: 29944948 DOI: 10.1016/j.brainresbull.2018.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 06/19/2018] [Accepted: 06/21/2018] [Indexed: 12/18/2022]
Abstract
The crucial role of the median preoptic nucleus (MnPO) in the maintenance of hydroelectrolytic balance and autonomic regulation have been highlighted. Recently, the participation of the MnPO in the control of sympathetic nerve activity was demonstrated in essential hypertension model. However, peculiarities on the neurochemical changes underlying the differential role of MnPO during hypertension remain to be clarified. Therefore, this study aimed to investigate the main excitatory pathways that modulate MnPO neurons in hypertensive rats. Spontaneously hypertensive rats (SHR) and rats submitted previously to the Goldblatt protocol (two kidneys; one clip; 2K1C) were used. Rats of both groups (250 to 350 g, n = 6) were anesthetized with urethane (1.2 g/kg,i.v.) and instrumented to record mean arterial pressure (MAP), heart rate (HR) and renal sympathetic nerve activity (RSNA). Nanoinjection (100 nl) of saline (NaCl, 150 mM), losartan (AT1 receptor antagonist; 10 mM) and kynurenic acid (glutamate receptor antagonist; 50 mM) into the MnPO were performed. In 2K1C rats, glutamatergic blockade promoted decreases in MAP and RSNA (-19.1 ± 0.9 mmHg, -21.6 ± 2.8%, p < 0.05) when compared to saline (-0.4 ± 0.6 mmHg, 0.2 ± 0.7%, p < 0.05). Angiotensinergic inhibition also reduced these parameters (-11.5 ± 1.2 mmHg, -10.5 ± 1.0%, p < 0.05) in 2K1C. In SHR, Kynurenic acid nanoinjections produced hypotension and sympathoinhibition (-21.0 ± 2.5 mmHg, -24.7 ± 2.4%, p < 0.05), as well losartan nanoinjections (-9.7 ± 1.2 mmHg; p < 0.05) and RSNA (-12.0 ± 2.4%, p < 0.05). These findings support the conclusion that a tonic excitatory neurotransmission exerted by angiotensin II, and mostly by glutamate in the MnPO could participate in the modulation of blood pressure and RSNA independent on whether hypertension is primarily neurogenic or is secondary to stenosis in renal artery.
Collapse
Affiliation(s)
- Aline A Mourão
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - Aryanne B Soares de Mello
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - Marina C Dos Santos Moreira
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - Karla L Rodrigues
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - Paulo R Lopes
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - Carlos H Xavier
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - Rodrigo M Gomes
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - André H Freiria-Oliveira
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil
| | - Graziela T Blanch
- School of Medicine, Pharmacy and Biomedicine, Pontifical Catholic University of Goias, Goiania, GO, Brazil
| | - Eduardo Colombari
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University, Araraquara, São Paulo, Brazil
| | - Gustavo R Pedrino
- Center for Neuroscience and Cardiovascular Research, Department of Physiological Sciences, Biological Sciences Institute, Federal University of Goias, Goiania, GO, Brazil.
| |
Collapse
|
24
|
Wunpathe C, Potue P, Maneesai P, Bunbupha S, Prachaney P, Kukongviriyapan U, Kukongviriyapan V, Pakdeechote P. Hesperidin Suppresses Renin-Angiotensin System Mediated NOX2 Over-Expression and Sympathoexcitation in 2K-1C Hypertensive Rats. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2018; 46:751-767. [PMID: 29754503 DOI: 10.1142/s0192415x18500398] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Hesperidin, a flavonoid derived from citrus fruits, possesses several beneficial effects including anti-oxidation and anti-inflammation. The aim of this study was to investigate the effects of hesperidin on the renin-angiotensin system (RAS) cascade that mediated oxidative stress and sympathoexcitation in two-kidney, one-clipped (2K-1C) hypertensive rats. 2K-1C hypertension was induced in male Sprague-Dawley rats. Hypertensive rats were treated with hesperidin at 20[Formula: see text]mg/kg or 40[Formula: see text]mg/kg or losartan at 10[Formula: see text]mg/kg beginning at three weeks after surgery and then continued for four weeks ([Formula: see text]/group). Hesperidin reduced blood pressure in a dose-dependent manner in hypertensive rats compared to untreated rats ([Formula: see text]). Increased plasma angiotensin converting enzyme (ACE) activity and angiotensin II levels, as well as, upregulated AT1 receptor protein expression in aortic tissues were attenuated in hypertensive rats treated with hesperidin. Hesperidin suppressed oxidative stress markers and NADPH oxidase over-expression, and restored plasma nitric oxide metabolites in 2K-1C rats. This was associated with improvement of the vascular response to acetylcholine in isolated mesenteric vascular beds and aortic rings from 2K-1C rats treated with hesperidin ([Formula: see text]). Enhancement of nerve-mediated vasoconstriction related to high plasma noradrenaline in the 2K-1C group was alleviated by hesperidin treatment ([Formula: see text]). Furthermore, losartan exhibited antihypertensive effects by suppressing the RAS cascade and oxidative stress and improved vascular dysfunction observed in 2K-1C rats ([Formula: see text]). Based on these results, it can be presumed that hesperidin is an antihypertensive agent. Its antihypertensive action might be associated with reducing RAS cascade-induced NOX2 over-expression and sympathoexcitation in 2K-1C hypertensive rats.
Collapse
Affiliation(s)
- Chutamas Wunpathe
- * Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,§ Cardiovascular Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Prapassorn Potue
- * Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,§ Cardiovascular Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Putcharawipa Maneesai
- * Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,§ Cardiovascular Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Sarawoot Bunbupha
- ¶ Faculty of Medicine, Mahasarakham University, Mahasarakham, Thailand
| | - Parichat Prachaney
- † Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,§ Cardiovascular Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Upa Kukongviriyapan
- * Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,§ Cardiovascular Research Group, Khon Kaen University, Khon Kaen, Thailand
| | | | - Poungrat Pakdeechote
- * Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,§ Cardiovascular Research Group, Khon Kaen University, Khon Kaen, Thailand
| |
Collapse
|
25
|
Haspula D, Clark MA. Molecular Basis of the Brain Renin Angiotensin System in Cardiovascular and Neurologic Disorders: Uncovering a Key Role for the Astroglial Angiotensin Type 1 Receptor AT1R. J Pharmacol Exp Ther 2018; 366:251-264. [PMID: 29752427 DOI: 10.1124/jpet.118.248831] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/08/2018] [Indexed: 12/13/2022] Open
Abstract
The central renin angiotensin system (RAS) is one of the most widely investigated cardiovascular systems in the brain. It is implicated in a myriad of cardiovascular diseases. However, studies from the last decade have identified its involvement in several neurologic abnormalities. Understanding the molecular functionality of the various RAS components can thus provide considerable insight into the phenotypic differences and mechanistic drivers of not just cardiovascular but also neurologic disorders. Since activation of one of its primary receptors, the angiotensin type 1 receptor (AT1R), results in an augmentation of oxidative stress and inflammatory cytokines, it becomes essential to investigate not just neuronal RAS but glial RAS as well. Glial cells are key homeostatic regulators in the brain and are critical players in the resolution of overt oxidative stress and neuroinflammation. Designing better and effective therapeutic strategies that target the brain RAS could well hinge on understanding the molecular basis of both neuronal and glial RAS. This review provides a comprehensive overview of the major studies that have investigated the mechanisms and regulation of the brain RAS, and it also provides insight into the potential role of glial AT1Rs in the pathophysiology of cardiovascular and neurologic disorders.
Collapse
Affiliation(s)
- Dhanush Haspula
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin (D.H.); and College of Pharmacy, Department of Pharmaceutical Sciences, Nova Southeastern University, Ft. Lauderdale, Florida (M.A.C.)
| | - Michelle A Clark
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin (D.H.); and College of Pharmacy, Department of Pharmaceutical Sciences, Nova Southeastern University, Ft. Lauderdale, Florida (M.A.C.)
| |
Collapse
|
26
|
Zafirovic S, Sudar-Milovanovic E, Obradovic M, Djordjevic J, Jasnic N, Borovic ML, Isenovic ER. Involvement of PI3K, Akt and RhoA in Oestradiol Regulation of Cardiac iNOS Expression. Curr Vasc Pharmacol 2018; 17:307-318. [PMID: 29437011 DOI: 10.2174/1570161116666180212142414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 02/06/2018] [Accepted: 02/07/2018] [Indexed: 01/12/2023]
Abstract
BACKGROUND Oestradiol is an important regulatory factor with several positive effects on the cardiovascular (CV) system. We evaluated the molecular mechanism of the in vivo effects of oestradiol on the regulation of cardiac inducible nitric oxide (NO) synthase (iNOS) expression and activity. METHODS Male Wistar rats were treated with oestradiol (40 mg/kg, intraperitoneally) and after 24 h the animals were sacrificed. The concentrations of NO and L-Arginine (L-Arg) were determined spectrophotometrically. For protein expressions of iNOS, p65 subunit of nuclear factor-κB (NFκB-p65), Ras homolog gene family-member A (RhoA), angiotensin II receptor type 1 (AT1R), insulin receptor substrate 1 (IRS-1), p85, p110 and protein kinase B (Akt), Western blot method was used. Coimmunoprecipitation was used for measuring the association of IRS-1 with the p85 subunit of phosphatidylinositol- 3-kinase (PI3K). The expression of iNOS messenger ribonucleic acid (mRNA) was measured with the quantitative real-time polymerase chain reaction (qRT-PCR). Immunohistochemical analysis of the tissue was used to detect localization and expression of iNOS in heart tissue. RESULTS Oestradiol treatment reduced L-Arg concentration (p<0.01), iNOS mRNA (p<0.01) and protein (p<0.001) expression, level of RhoA (p<0.05) and AT1R (p<0.001) protein. In contrast, plasma NO (p<0.05), Akt phosphorylation at Thr308 (p<0.05) and protein level of p85 (p<0.001) increased after oestradiol treatment. CONCLUSION Our results suggest that oestradiol in vivo regulates cardiac iNOS expression via the PI3K/Akt signaling pathway, through attenuation of RhoA and AT1R.
Collapse
Affiliation(s)
- Sonja Zafirovic
- Institute of Nuclear Sciences "Vinca", Department of Radiobiology and Molecular Genetics, University of Belgrade, Belgrade, Serbia
| | - Emina Sudar-Milovanovic
- Institute of Nuclear Sciences "Vinca", Department of Radiobiology and Molecular Genetics, University of Belgrade, Belgrade, Serbia
| | - Milan Obradovic
- Institute of Nuclear Sciences "Vinca", Department of Radiobiology and Molecular Genetics, University of Belgrade, Belgrade, Serbia
| | - Jelena Djordjevic
- Institute of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Nebojsa Jasnic
- Institute of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Milica Labudovic Borovic
- Institute of Histology and Embryology "Aleksandar D. Kostic", Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Esma R Isenovic
- Institute of Nuclear Sciences "Vinca", Department of Radiobiology and Molecular Genetics, University of Belgrade, Belgrade, Serbia.,Faculty of Stomatology, Pancevo, University Business Academy, Novi Sad, Serbia
| |
Collapse
|
27
|
Nunes DV, Costa CA, De Bem GF, Cordeiro VS, Santos IB, Carvalho LC, Jordão AK, Cunha AC, Ferreira VF, Moura RS, Resende AC, Ognibene DT. Tempol, a superoxide dismutase-mimetic drug, prevents chronic ischemic renal injury in two-kidney, one-clip hypertensive rats. Clin Exp Hypertens 2018; 40:721-729. [PMID: 29359965 DOI: 10.1080/10641963.2018.1425423] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Tempol, a superoxide dismutase-mimetic drug, has been shown to attenuate radical-induced damage, exerting beneficial effects in the animal models of oxidative stress and hypertension. This study evaluated the effect of Tempol on renal structural and functional alterations in two-Kidney, one-Clip hypertensive rats. In this study, young male Wistar rats had the left kidney clipped (2K1C), and sham-operated animals (Sham) were used as controls. Animals received Tempol (1mmol/L in drinking water) or vehicle for 5 weeks. Systolic blood pressure was evaluated once a week. At the end of the experimental protocol, the animals were placed in metabolic cages to collect urine (24h) and then anesthetized with thiopental (70mg/kg i.p.) to collect blood by puncturing the descending aorta for biochemical analysis, and the clipped kidney for morphological and immunohistochemical analyses. The vasodilator effect of Tempol was evaluated in mesenteric arterial bed (MAB) isolated from adult Wistar rats. The chronic treatment with Tempol prevented the development of hypertension and the increased plasma levels of urea, creatinine, and 8-isoprostane in 2K1C animals. Tempol also improved both glomeruli number and kidney volume to normal levels in the 2K1C+Tempol group. In addition, the treatment prevented the increased collagen deposition and immunostaining for renin, caspase-3, and 8-isoprostane in the stenotic kidney of 2K1C animals. Moreover, Tempol induced a dose-dependent vasodilator response in MAB from Wistar rats. These results suggest that Tempol protects the stenotic kidney against chronic ischemic renal injury and prevents renal dysfunction in the 2K1C model, probably through its antioxidant, vasodilator and antihypertensive actions.
Collapse
Affiliation(s)
- Douglas Vq Nunes
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Cristiane A Costa
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Graziele F De Bem
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Viviane Sc Cordeiro
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Izabelle B Santos
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Lenize Crm Carvalho
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Alessandro K Jordão
- b University Unit of Pharmacy, State University of the West Zone , Rio de Janeiro , RJ , Brazil
| | - Anna C Cunha
- c Department of Organic Chemistry , Fluminense Federal University , Niterói , RJ , Brazil
| | - Vitor F Ferreira
- c Department of Organic Chemistry , Fluminense Federal University , Niterói , RJ , Brazil
| | - Roberto S Moura
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Angela C Resende
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| | - Dayane T Ognibene
- a Department of Pharmacology , Institute of Biology, Rio de Janeiro State University , Rio de Janeiro , RJ , Brazil
| |
Collapse
|
28
|
Combinative effect of sardine peptides and quercetin alleviates hypertension through inhibition of angiotensin I converting enzyme activity and inflammation. Food Res Int 2017; 100:579-585. [PMID: 28873724 DOI: 10.1016/j.foodres.2017.07.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/27/2017] [Accepted: 07/06/2017] [Indexed: 11/21/2022]
Abstract
Hypertension had relation to angiotensin I converting enzyme (ACE) activity and inflammation. In our previous research, sardine peptides (SP) with ACE inhibitory activity were prepared. However, the combinative effect of SP and quercetin (QC) on hypertension alleviation was still unknown. In the present study, the antihypertensive effect of SP and QC was discovered and the optimal proportion of SP and QC (v/v=8:2, with 20.00mg/mL of SP and 12.99μg/mL of QC for their original concentrations) was screened on ACE activity inhibition in vitro. And the in vivo experiment supported it by indicating that the mixture reduced the systolic blood pressure, heart, left ventricular and kidney weight and their corresponding indices, serum ACE activity, angiotensin-II (ANG-II) and tumor necrosis factor-α (TNF-α) (in high dose) concentration in SHR rats. Besides, the mixture also lowers NO, TNF-α andinterleukin-6 (IL-6) concentration significantly in vitro. Hence, the combinative effect of SP and QC in optimal proportion had stronger inhibition on ACE activity than SP or QC alone, and could alleviate hypertension through inhibition of ACE activity and inflammation.
Collapse
|
29
|
Lincevicius GS, Shimoura CG, Nishi EE, Oliveira T, Cespedes JG, Bergamaschi CT, Campos RR. Differential effects of renal denervation on arterial baroreceptor function in Goldblatt hypertension model. Auton Neurosci 2017; 208:43-50. [PMID: 28688830 DOI: 10.1016/j.autneu.2017.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 06/09/2017] [Accepted: 06/19/2017] [Indexed: 01/19/2023]
Abstract
Sympathetic vasomotor activity is significantly increased in renovascular hypertension. Renal denervation (DnX) has emerged as a novel therapy for resistant hypertension to drug therapy. However, the underlying mechanisms regarding the reduction in blood pressure (BP) after DnX remain unclear. Thus, the aim of this study was to evaluate the effects of DnX of a clipped kidney on the baseline and baroreceptor reflex control of post-ganglionic sympathetic activity to the contralateral kidney (rSNA) and lumbar (lSNA) nerves in Goldblatt hypertensive rats (2K1C). Renal denervation of an ischaemic kidney (DxX - all visible bundles of nerves were dissected - 10% phenol) was performed 5weeks after clipping (gap width: 0.2mm). Ten days after DnX, BP was significantly reduced (16%) in the 2K1C compared with the undenervated 2K1C (p<0.05). DnX significantly reduced basal rSNA (control group (CT): 110±8, n=14; 2K1C: 150±8, n=12; 2K1C DnX: 89±7, spikes per second (spikes/s); p<0.05, n=8) and lSNA (CT: 137±8, n=8; 2K1C: 202±7, n=11; 2K1C DnX: 131±7, spikes/s; p<0.05, n=8) only in 2K1C rats. DnX significantly improved the arterial baroreceptor sensitivity of rSNA (CT: -2.3±0.2, n=11; 2K1C: -0.7±0.1, n=8; 2K1C DnX: -1.5±0.2, spikes/s/mmHg; p<0.05, n=5) and heart rate for tachycardic response (CT: -3.9±0.5, n=7; 2K1C: -1.9±0.1, n=8; 2K1C DnX: -3.3±0.4, bpm/mmHg; p<0.05, n=8), but not for lSNA in 2K1C rats. The results show that DnX normalized baseline sympathetic vasomotor activity to the lumbar and renal nerves, followed by a differential improvement in the arterial baroreceptor sensitivity. Whether the baroreceptor function sensitivity improvement induced by DnX is a cause or a consequence of BP reduction remains to be determined.
Collapse
Affiliation(s)
- Gisele S Lincevicius
- Cardiovascular Division, Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Caroline G Shimoura
- Cardiovascular Division, Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Erika E Nishi
- Cardiovascular Division, Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Tales Oliveira
- Cardiovascular Division, Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Juliana G Cespedes
- Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, Campus São José dos Campos, Brazil
| | - Cássia T Bergamaschi
- Cardiovascular Division, Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Ruy R Campos
- Cardiovascular Division, Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil.
| |
Collapse
|
30
|
Shimoura CG, Lincevicius GS, Nishi EE, Girardi ACC, Simon KA, Bergamaschi CT, Campos RR. Increased Dietary Salt Changes Baroreceptor Sensitivity and Intrarenal Renin-Angiotensin System in Goldblatt Hypertension. Am J Hypertens 2017; 30:28-36. [PMID: 27629265 DOI: 10.1093/ajh/hpw107] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 08/18/2016] [Accepted: 08/19/2016] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Renovascular hypertension (2-kidney 1-clip model (2K1C)) is characterized by renin-angiotensin system (RAS) activation. Increased Angiotensin II (AngII) leads to sympathoexcitation, oxidative stress, and alterations in sodium and water balance. AIM The aim of this study was to evaluate whether a discrete increase in sodium chloride intake in 2K1C rats leads to changes in cardiovascular and autonomic function, oxidative stress, and renin angiotensin aldosterone system. METHODS After 4 weeks of induction of hypertension, rats were fed a normal sodium diet (0.4% NaCl) or a high-sodium diet (2% NaCl) for 2 consecutive weeks. Experiments were carried out for 6 weeks after clipping. Mean arterial pressure (MAP), renal sympathetic nerve activity (rSNA), arterial baroreflex control of rSNA, and heart rate (HR) were assessed. Thiobarbituric acid reactive substances and glutathione were measured as indicators of systemic oxidative stress. Angiostensin-converting enzyme (ACE), ACE2, and angiotensinogen were evaluated in clipped and unclipped kidneys as also urinary angiotensinogen and plasma renin activity. Angiotensinogen, plasma renin activity (PRA) and angiotensin-converting enzyme (ACE) and ACE2 in clipped and unclipped kidneys were evaluated. RESULTS High-sodium diet did not change systemic oxidative stress, and basal values of MAP, HR, or rSNA; however, increased renal (-0.7±0.2 vs. -1.5±0.1 spikes/s/mm Hg) and cardiac (-0.9±0.14 vs. -1.5±0.14 bpm/mm Hg) baroreceptor reflex sensitivity in 2K1C rats. Although there was no alteration in PRA, a high-salt diet significantly decreased urinary angiotensinogen, ACE, and ACE2 expressions in the clipped and unclipped kidneys. CONCLUSIONS Increased arterial baroreceptor control associated with a suppression of the intrarenal RAS in the 2K1C rats on high-salt diet provide a salt-resistant effect on hypertension and sympathoexcitation in renovascular hypertensive rats.
Collapse
Affiliation(s)
- Caroline G Shimoura
- Cardiovascular Division-Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Gisele S Lincevicius
- Cardiovascular Division-Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Erika E Nishi
- Cardiovascular Division-Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Adriana C C Girardi
- Heart Institute (InCor) University of São Paulo Medical School, São Paulo, São Paulo, Brazil
| | - Karin A Simon
- Department of Biological Sciences, Universidade Federal de São Paulo, Diadema, Brazil
| | - Cassia T Bergamaschi
- Cardiovascular Division-Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ruy R Campos
- Cardiovascular Division-Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil;
| |
Collapse
|
31
|
Abstract
Hypertension affects over 25 % of the population with the incidence continuing to rise, due in part to the growing obesity epidemic. Chronic elevations in sympathetic nerve activity (SNA) are a hallmark of the disease and contribute to elevations in blood pressure through influences on the vasculature, kidney, and heart (i.e., neurogenic hypertension). In this regard, a number of central nervous system mechanisms and neural pathways have emerged as crucial in chronically elevating SNA. However, it is important to consider that "sympathetic signatures" are present, with differential increases in SNA to regional organs that are dependent upon the disease progression. Here, we discuss recent findings on the central nervous system mechanisms and autonomic regulatory networks involved in neurogenic hypertension, in both non-obesity- and obesity-associated hypertension, with an emphasis on angiotensin-II, salt, oxidative and endoplasmic reticulum stress, inflammation, and the adipokine leptin.
Collapse
|
32
|
Raquel HDA, Masson GS, Barna BF, Zanluqui NG, Pinge-Filho P, Michelini LC, Martins-Pinge MC. Swimming Training Modulates Nitric Oxide-Glutamate Interaction in the Rostral Ventrolateral Medulla in Normotensive Conscious Rats. Front Physiol 2016; 7:221. [PMID: 27378935 PMCID: PMC4904284 DOI: 10.3389/fphys.2016.00221] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 05/27/2016] [Indexed: 12/20/2022] Open
Abstract
We evaluated the effects of swimming training on nitric oxide (NO) modulation to glutamate microinjection within the rostral ventrolateral medulla (RVLM) in conscious freely moving rats. Male Wistar rats were submitted to exercise training (Tr) by swimming or kept sedentary (Sed) for 4 weeks. After the last training session, RVLM guide cannulas and arterial/venous catheters were chronically implanted. Arterial pressure (AP), heart rate (HR), and baroreflex control of HR (loading/unloading of baroreceptors) were recorded in conscious rats at rest. Pressor response to L-glutamate in the RVLM was compared before and after blockade of local nitric oxide (NO) production. In other Tr and Sed groups, brain was harvested for gene (qRT-PCR) and protein (immunohistochemistry) expression of NO synthase (NOS) isoforms and measurement of NO content (nitrite assay) within the RVLM. Trained rats exhibited resting bradycardia (average reduction of 9%), increased baroreflex gain (Tr: −4.41 ± 0.5 vs. Sed: −2.42 ± 0.31 b/min/mmHg), and unchanged resting MAP. The pressor response to glutamate was smaller in the Tr group (32 ± 4 vs. 53 ± 2 mmHg, p < 0.05); this difference disappeared after RVLM pretreatment with carboxy-PTIO (NO scavenger), Nw-Propyl-L-Arginine and L-NAME (NOS inhibitors). eNOS immunoreactivity observed mainly in RVLM capillaries was higher in Tr, but eNOS gene expression was reduced. nNOS gene and protein expression was slightly reduced (−29 and −9%, respectively, P > 0.05). Also, RVLM NO levels were significantly reduced in Tr (−63% vs. Sed). After microinjection of a NO-donor, the attenuated pressor response of L-glutamate in Tr group was restored. Data indicate that swimming training by decreasing RVLM NO availability and glutamatergic neurotransmission to locally administered glutamate may contribute to decreased sympathetic activity in trained subjects.
Collapse
Affiliation(s)
- Hiviny de A Raquel
- Department of Physiological Sciences, Center of Biological Sciences, State University of Londrina Londrina, Brazil
| | - Gustavo S Masson
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo, Brazil
| | - Barbara Falquetto Barna
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo, Brazil
| | - Nágela G Zanluqui
- Department of Pathological Sciences, Center of Biological Sciences, State University of Londrina Londrina, Brazil
| | - Phileno Pinge-Filho
- Department of Pathological Sciences, Center of Biological Sciences, State University of Londrina Londrina, Brazil
| | - Lisete C Michelini
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo, Brazil
| | - Marli C Martins-Pinge
- Department of Physiological Sciences, Center of Biological Sciences, State University of Londrina Londrina, Brazil
| |
Collapse
|
33
|
Biancardi VC, Stern JE. Compromised blood-brain barrier permeability: novel mechanism by which circulating angiotensin II signals to sympathoexcitatory centres during hypertension. J Physiol 2016; 594:1591-600. [PMID: 26580484 PMCID: PMC4799983 DOI: 10.1113/jp271584] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 10/23/2015] [Indexed: 12/14/2022] Open
Abstract
Angiotensin II (AngII) is a pivotal peptide implicated in the regulation of blood pressure. In addition to its systemic vascular and renal effects, AngII acts centrally to modulate the activities of neuroendocrine and sympathetic neuronal networks, influencing in turn sympatho-humoral outflows to the circulation. Moreover, a large body of evidence supports AngII signalling dysregulation as a key mechanism contributing to exacerbated sympathoexcitation during hypertension. Due to its hydrophilic actions, circulating AngII does not cross the blood-brain barrier (BBB), signalling to the brain via the circumventricular organs which lack a tight BBB. In this review, we present and discuss recent studies from our laboratory showing that elevated circulating levels of AngII during hypertension result in disruption of the BBB integrity, allowing access of circulating AngII to critical sympathoexcitatory brain centres such as the paraventricular nucleus of the hypothalamus and the rostral ventrolateral medulla. We propose the novel hypothesis that AngII-driven BBB breakdown constitutes a complementary mechanism by which circulating AngII, working in tandem with the central renin-angiotensin system, further exacerbates sympatho-humoral activation during hypertension. These results are discussed within the context of a growing body of evidence in the literature supporting AngII as a pro-inflammatory signal, and brain microglia as key cell targets mediating central AngII actions during hypertension.
Collapse
Affiliation(s)
- V C Biancardi
- Department of Physiology, Georgia Regents University, Augusta, GA, USA
| | - J E Stern
- Department of Physiology, Georgia Regents University, Augusta, GA, USA
| |
Collapse
|
34
|
Oliveira-Sales EB, Colombari E, Abdala AP, Campos RR, Paton JFR. Sympathetic overactivity occurs before hypertension in the two-kidney, one-clip model. Exp Physiol 2015; 101:67-80. [PMID: 26537847 DOI: 10.1113/ep085390] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 11/03/2015] [Indexed: 12/21/2022]
Abstract
Our knowledge of mechanisms responsible for both the development and the maintenance of hypertension remains incomplete in the Goldblatt (two-kidney, one-clip; 2K1C) model. We tested the hypothesis that elevated sympathetic nerve activity (SNA) occurs before the onset of hypertension in 2K1C rats, considering the time course of the increase in SNA in relationship to the onset of the hypertension. We used a decorticated in situ working heart-brainstem preparation of three groups of male Wistar rats, namely sham-operated animals (SHAM, n = 7) and animals 3 weeks post-2K1C, of which some were hypertensive (2K1C-H, n = 6) and others normotensive (2K1C-N, n = 9), as determined in vivo a priori. Perfusion pressure was higher in both 2K1C groups (2K1C-H, 76 ± 1 mmHg; 2K1C-N, 74 ± 3 mmHg; versus SHAM, 60 ± 2 mmHg, P < 0.05). The SNA was significantly elevated in both 2K1C groups (2K1C-H, 47.7 ± 6.1 μV; 2K1C-N, 32.8 ± 2.8 μV; versus SHAM, 20.5 ± 2.5 μV, P < 0.05) owing to its increased respiratory modulation; the chemoreflex was augmented and baroreflex depressed. Precollicular transection reduced SNA in all groups (2K1C-H, -32.5 ± 7.5%; 2K1C-NH, -48 ± 6.9%; versus SHAM, -13.2 ± 1%, P < 0.05). Subsequent medullary spinal cord transection abolished SNA in both SHAM and 2K1C-N groups, but decreased it by only 57 ± 5.5% in 2K1C-H preparations. Thus, SNA is raised before the onset of hypertension, by the third week after renal artery clipping, and this originates, in part, from its enhanced respiratory modulation. Spinal circuits contribute to the elevation of SNA in the 2K1C model, but only after hypertension has developed.
Collapse
Affiliation(s)
- Elizabeth B Oliveira-Sales
- School of Physiology & Pharmacology, Bristol Heart Institute, University of Bristol, Bristol, UK.,Department of Physiology, Federal University of Sao Paulo, UNIFESP, SP, Brazil
| | - Eduardo Colombari
- School of Physiology & Pharmacology, Bristol Heart Institute, University of Bristol, Bristol, UK.,Department of Physiology & Pathology, School of Dentistry of Araraquara, São Paulo State University, UNESP, Araraquara, SP, Brazil
| | - Ana Paula Abdala
- School of Physiology & Pharmacology, Bristol Heart Institute, University of Bristol, Bristol, UK
| | - Ruy R Campos
- Department of Physiology, Federal University of Sao Paulo, UNIFESP, SP, Brazil
| | - Julian F R Paton
- School of Physiology & Pharmacology, Bristol Heart Institute, University of Bristol, Bristol, UK
| |
Collapse
|
35
|
Oliveira-Sales EB, Boim MA. Mesenchymal stem cells and chronic renal artery stenosis. Am J Physiol Renal Physiol 2015; 310:F6-9. [PMID: 26538439 DOI: 10.1152/ajprenal.00341.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Renal artery stenosis is the main cause of renovascular hypertension and results in ischemic nephropathy characterized by inflammation, oxidative stress, microvascular loss, and fibrosis with consequent functional failure. Considering the limited number of strategies that effectively control renovascular hypertension and restore renal function, we propose that cell therapy may be a promising option based on the regenerative and immunosuppressive properties of stem cells. This review addresses the effects of mesenchymal stem cells (MSC) in an experimental animal model of renovascular hypertension known as 2 kidney-1 clip (2K-1C). Significant benefits of MSC treatment have been observed on blood pressure and renal structure of the stenotic kidney. The mechanisms involved are discussed.
Collapse
Affiliation(s)
| | - Mirian A Boim
- Nephrology Division, Federal University of São Paulo, São Paulo, Brazil
| |
Collapse
|
36
|
Qiao YF, Guo WJ, Li L, Shao S, Qiao X, Shao JJ, Zhang Q, Li RS, Wang LH. Melatonin attenuates hypertension-induced renal injury partially through inhibiting oxidative stress in rats. Mol Med Rep 2015; 13:21-6. [PMID: 26531807 PMCID: PMC4686099 DOI: 10.3892/mmr.2015.4495] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 06/25/2015] [Indexed: 12/31/2022] Open
Abstract
The aim of the present study was to investigate the protective effects of melatonin (MLT) on hypertension-induced renal injury and identify its mechanism of action. Twenty-four healthy male Wistar rats were divided into a sham control group (n=8), which was subjected to sham operation and received vehicle treatment (physiological saline intraperitoneally at 0.1 ml/100 g), a vehicle group (n=8), which was subjected to occlusion of the left renal artery and vehicle treatment, and the MLT group (n=8), which was subjected to occlusion of the left renal artery and treated with MLT (10 mg/kg/day). Pathological features of the renal tissues were determined using hematoxylin and eosin staining and Masson staining. Urine protein, serum creatinine (Scr), superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. Immunohistochemical analysis was performed to determine the expression of heme oxygenase-1 (HO-1), intercellular adhesion molecule-1 (ICAM-1), inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS). Furthermore, reverse transcription polymerase chain reaction was conducted to determine the mRNA expression of HO-1, ICAM-1, eNOS and iNOS. A marked decrease in blood pressure was noticed in the MLT group at week 4 compared with that of the vehicle group (P<0.01). Furthermore, MLT treatment attenuated the infiltration of inflammatory cells and oedema/atrophy of renal tubules. MLT attenuated hypertension-induced increases in urine protein excretion, serum creatinine and MDA as well as decreases in SOD activity in renal tissues. Furthermore, MLT attenuated hypertension-induced increases in iNOS and ICAM-1 as well as decreases in eNOS and HO-1 expression at the mRNA and protein level. In conclusion, the results of the present study indicated that MLT had protective roles in hypertension-induced renal injury. Its mechanism of action is, at least in part, associated with the inhibition of oxidative stress.
Collapse
Affiliation(s)
- Yu-Feng Qiao
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Wen-Juan Guo
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Lu Li
- Department of Nephrology, Baoding No. 1 Hospital, Baoding, Hebei 071000, P.R. China
| | - Shan Shao
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Xi Qiao
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Jin-Jin Shao
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Qiong Zhang
- Department of Nephrology, Shanxi People's Hospital, Taiyuan, Shanxi 030001, P.R. China
| | - Rong-Shan Li
- Department of Nephrology, Shanxi People's Hospital, Taiyuan, Shanxi 030001, P.R. China
| | - Li-Hua Wang
- Department of Nephrology, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| |
Collapse
|
37
|
Lincevicius GS, Shimoura CG, Nishi EE, Perry JC, Casarini DE, Gomes GN, Bergamaschi CT, Campos RR. Aldosterone Contributes to Sympathoexcitation in Renovascular Hypertension. Am J Hypertens 2015; 28:1083-90. [PMID: 25628418 DOI: 10.1093/ajh/hpu300] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 12/18/2014] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Although angiotensin II (Ang II) is essential to the development of renovascular hypertension, aldosterone plays a role as well. Recent studies have demonstrated a cross-talk between Ang II type 1 and mineralocorticoid receptors in the brain and kidneys. However, the role of aldosterone in the autonomic and renal dysfunction of renovascular hypertension is not well understood. AIM The current study evaluated whether aldosterone contributes to cardiovascular and renal dysfunction in the 2 kidney-1 clip (2K1C) model. METHODS Mean arterial pressure (MAP) and baroreceptor reflex for control of the heart rate were evaluated in 2K1C treated or not treated with spironolactone (200mg/kg/day, 7 days). Tonic and reflex control of renal sympathetic nerve activity (rSNA) were assessed in urethane-anaesthetized rats. Plasma renin activity (PRA), kidney renin protein expression, renal injury, and central AT1 receptor protein expression were assessed. RESULTS Spiro reduced MAP (198±4 vs. 170±9mm Hg; P < 0.05), normalized rSNA (147±9 vs. 96±10 pps; P < 0.05), and increased renal baroreceptor reflex sensitivity in the 2K1C rats. Spiro reduced α-smooth muscle actin expression in the nonclipped kidney in the 2K1C group (5±0.6 vs. 1.1±0.2%; P < 0.05). There was no change in PRA; however, a decrease in renin protein expression in the nonclipped kidney was found in the 2K1C treated group (217±30 vs. 160±19%; P < 0.05). Spiro treatment decreased AT1 receptor in the central nervous system (CNS) only in 2K1C rats (138±10 vs. 84±12%; P < 0.05). CONCLUSION Aldosterone contributes to autonomic dysfunction and intrarenal injury in 2K1C, these effects are mediated by the CNS.
Collapse
Affiliation(s)
- Gisele S Lincevicius
- Department of Physiology - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Caroline G Shimoura
- Department of Physiology - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Erika E Nishi
- Department of Physiology - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Juliana C Perry
- Department of Psychobiology - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Dulce E Casarini
- Nephrology Division, Department of Medicine - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Guiomar N Gomes
- Department of Physiology - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Cássia T Bergamaschi
- Department of Physiology - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ruy R Campos
- Department of Physiology - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil;
| |
Collapse
|
38
|
Sousa LE, Magalhães WG, Bezerra FS, Santos RAS, Campagnole-Santos MJ, Isoldi MC, Alzamora AC. Exercise training restores oxidative stress and nitric oxide synthases in the rostral ventrolateral medulla of renovascular hypertensive rats. Free Radic Res 2015; 49:1335-43. [DOI: 10.3109/10715762.2015.1069291] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
39
|
Campos RR, Oliveira-Sales EB, Nishi EE, Paton JFR, Bergamaschi CT. Mechanisms of renal sympathetic activation in renovascular hypertension. Exp Physiol 2015; 100:496-501. [DOI: 10.1113/expphysiol.2014.079855] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/26/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Ruy R. Campos
- Department of Physiology, Cardiovascular Division; Universidade Federal de São Paulo; São Paulo Brazil
| | | | - Erika E. Nishi
- Department of Physiology, Cardiovascular Division; Universidade Federal de São Paulo; São Paulo Brazil
| | - Julian F. R. Paton
- School of Physiology & Pharmacology, Bristol CardioVascular; University of Bristol; Medical Sciences Building Bristol BS8 1TD UK
| | - Cassia T. Bergamaschi
- Department of Physiology, Cardiovascular Division; Universidade Federal de São Paulo; São Paulo Brazil
| |
Collapse
|
40
|
Oliveira-Sales EB, Varela VA, Bergamaschi CT, Campos RR, Boim MA. Effects of mesenchymal stem cells in renovascular hypertension. Exp Physiol 2015; 100:491-5. [DOI: 10.1113/expphysiol.2014.080531] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/19/2015] [Indexed: 01/21/2023]
Affiliation(s)
- Elizabeth B. Oliveira-Sales
- Department of Medicine; Renal Division; Federal University of Sao Paulo; Sao Paulo Brazil
- Department of Physiology; Cardiovascular Division; Federal University of Sao Paulo; Sao Paulo Brazil
| | - Vanessa A. Varela
- Department of Medicine; Renal Division; Federal University of Sao Paulo; Sao Paulo Brazil
| | - Cassia T. Bergamaschi
- Department of Physiology; Cardiovascular Division; Federal University of Sao Paulo; Sao Paulo Brazil
| | - Ruy R. Campos
- Department of Physiology; Cardiovascular Division; Federal University of Sao Paulo; Sao Paulo Brazil
| | - Mirian A. Boim
- Department of Medicine; Renal Division; Federal University of Sao Paulo; Sao Paulo Brazil
| |
Collapse
|
41
|
Nishi EE, Bergamaschi CT, Campos RR. The crosstalk between the kidney and the central nervous system: the role of renal nerves in blood pressure regulation. Exp Physiol 2015; 100:479-84. [PMID: 25599970 DOI: 10.1113/expphysiol.2014.079889] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 12/09/2014] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the topic of this review? This review describes the role of renal nerves as the key carrier of signals from the kidneys to the CNS and vice versa; the brain and kidneys communicate through this carrier to maintain homeostasis in the body. What advances does it highlight? Whether renal or autonomic dysfunction is the predominant contributor to systemic hypertension is still debated. In this review, we focus on the role of the renal nerves in a model of renovascular hypertension. The sympathetic nervous system influences the renal regulation of arterial pressure and body fluid composition. Anatomical and physiological evidence has shown that sympathetic nerves mediate changes in urinary sodium and water excretion by regulating the renal tubular water and sodium reabsorption throughout the nephron, changes in the renal blood flow and the glomerular filtration rate by regulating the constriction of renal vasculature, and changes in the activity of the renin-angiotensin system by regulating the renin release from juxtaglomerular cells. Additionally, renal sensory afferent fibres project to the autonomic central nuclei that regulate blood pressure. Hence, renal nerves play a key role in the crosstalk between the kidneys and the CNS to maintain homeostasis in the body. Therefore, the increased sympathetic nerve activity to the kidney and the renal afferent nerve activity to the CNS may contribute to the outcome of diseases, such as hypertension.
Collapse
Affiliation(s)
- Erika E Nishi
- Department of Physiology, Cardiovascular Division, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | | |
Collapse
|
42
|
Towiwat P, Phattanarudee S, Maher TJ, Ally A. Modulation of inducible nitric oxide synthase (iNOS) expression and cardiovascular responses during static exercise following iNOS antagonism within the ventrolateral medulla. Mol Cell Biochem 2014; 398:185-94. [PMID: 25234194 DOI: 10.1007/s11010-014-2218-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 09/12/2014] [Indexed: 10/24/2022]
Abstract
Previous reports indicate that inducible nitric oxide synthase (iNOS) blockade within the rostral ventrolateral medulla (RVLM) and caudal ventrolateral medulla (CVLM) differentially modulated cardiovascular responses, medullary glutamate, and GABA concentrations during static skeletal muscle contraction. In the current study, we determined the role of iNOS antagonism within the RVLM and CVLM on cardiovascular responses and iNOS protein expression during the exercise pressor reflex in anesthetized rats. Following 120 min of bilateral microdialysis of a selective iNOS antagonist, aminoguanidine (AGN; 10 µM), into the RVLM, the pressor responses were attenuated by 72 % and changes in heart rate were reduced by 38 % during a static muscle contraction. Furthermore, western blot analysis of iNOS protein abundance within the RVLM revealed a significant attenuation when compared to control animals. In contrast, bilateral administration of AGN (10 µM) into the CVLM augmented the increases in mean arterial pressure by 60 % and potentiated changes in heart rate by 61 % during muscle contractions, but did not alter expression of the iNOS protein within the CVLM. These results demonstrate that iNOS protein expression within the ventrolateral medulla is differentially regulated by iNOS blockade that may, in part, contribute to the modulation of cardiovascular responses during static exercise.
Collapse
Affiliation(s)
- Pasarapa Towiwat
- Department of Pharmacology and Physiology, Chulalongkorn University, Bangkok, 10330, Thailand
| | | | | | | |
Collapse
|
43
|
Abstract
SIGNIFICANCE There is now compelling evidence to substantiate the notion that by depressing baroreflex regulation of blood pressure and augmenting central sympathetic outflow through their actions on the nucleus tractus solitarii (NTS) and rostral ventrolateral medulla (RVLM), brain stem nitric oxide synthase (NOS) and reactive oxygen species (ROS) are important contributing factors to neural mechanisms of hypertension. This review summarizes our contemporary views on the impact of NOS and ROS in the NTS and RVLM on neurogenic hypertension, and presents potential antihypertensive strategies that target brain stem NOS/ROS signaling. RECENT ADVANCES NO signaling in the brain stem may be pro- or antihypertensive depending on the NOS isoform that generates this gaseous moiety and the site of action. Elevation of the ROS level when its production overbalances its degradation in the NTS and RVLM underlies neurogenic hypertension. Interventional strategies with emphases on alleviating the adverse actions of these molecules on blood pressure regulation have been investigated. CRITICAL ISSUES The pathological roles of NOS in the RVLM and NTS in neural mechanisms of hypertension are highly complex. Likewise, multiple signaling pathways underlie the deleterious roles of brain-stem ROS in neurogenic hypertension. There are recent indications that interactions between brain stem ROS and NOS may play a contributory role. FUTURE DIRECTIONS Given the complicity of action mechanisms of brain-stem NOS and ROS in neural mechanisms of hypertension, additional studies are needed to identify the most crucial therapeutic target that is applicable not only in animal models but also in patients suffering from neurogenic hypertension.
Collapse
Affiliation(s)
- Samuel H H Chan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital , Kaohsiung, Taiwan, Republic of China
| | | |
Collapse
|
44
|
Vemuganti R. All's well that transcribes well: non-coding RNAs and post-stroke brain damage. Neurochem Int 2013; 63:438-49. [PMID: 23954844 PMCID: PMC3805745 DOI: 10.1016/j.neuint.2013.07.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 07/26/2013] [Accepted: 07/28/2013] [Indexed: 12/13/2022]
Abstract
The mammalian genome is replete with various classes of non-coding (nc) RNA genes. Many of them actively transcribe, and their relevance to CNS diseases is just beginning to be understood. CNS is one of the organs in the body that shows very high ncRNAs activity. Recent studies demonstrated that cerebral ischemia rapidly changes the expression profiles of different classes of ncRNAs: including microRNA, long noncoding RNA and piwi-interacting RNA. Several studies further showed that post-ischemic neuronal death and/or plasticity/regeneration can be altered by modulating specific microRNAs. These studies are of interest for therapeutic development as they may contribute to identifying new ncRNA targets that can be modulated to prevent secondary brain damage after stroke.
Collapse
Affiliation(s)
- Raghu Vemuganti
- Department of Neurological Surgery, University of Wisconsin, Madison, WI, USA.
| |
Collapse
|
45
|
Nishi EE, Bergamaschi CT, Oliveira-Sales EB, Simon KA, Campos RR. Losartan reduces oxidative stress within the rostral ventrolateral medulla of rats with renovascular hypertension. Am J Hypertens 2013; 26:858-65. [PMID: 23485486 DOI: 10.1093/ajh/hpt037] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Previous studies showed that the microinjection of antioxidants or the overexpression of superoxide dismutase within the rostral ventrolateral medulla (RVLM) reduces hypertension and sympathoexcitation in the 2-kidney, 1-clip (2K-1C) model. In this study, we hypothesized that angiotensin II (ANG II) type 1 receptor (AT1R) is involved in the oxidative stress within the RVLM and contributes to cardiovascular dysfunction in renovascular hypertension. METHODS Losartan (30mg/kg/day, oral gavage) was administered for 7 consecutive days by week 5 after implantation of the clip (gap width = 0.2mm). Mean arterial pressure, baroreflex, and renal sympathetic nerve activity (rSNA) were evaluated. Superoxide production was evaluated by dihydroethidium (DHE) staining within the RVLM and within a control area. Systemic oxidative stress was characterized by measurement of thiobarbituric acid reactive substances (TBARS) and total glutathione (tGSH) in the blood. RESULTS AT1R blockade significantly (P < 0.05) reduced hypertension by approximately 20% (n = 11) and sympathoexcitation to the kidneys by approximately 41% (n = 6) in the 2K-1C rats. Losartan treatment increased the baroreflex sensitivity of rSNA to pressor (67%) and depressor (140%) stimuli in the 2K-1C rats. AT1R blockade caused a significant (66%) reduction in DHE staining within the RVLM but not within the control area, reduced plasma TBARS (from 1.6±0.1 to 1.0±0.1 nmol/ml), and increased tGSH (from 3.4±0.4 to 5.2±0.3 μmol/g Hb) in the 2K-1C group only. CONCLUSIONS Our findings suggest that the beneficial effects of ANG II blockade in renovascular hypertension are partly due to preferential reduction of oxidative stress in the RVLM.
Collapse
Affiliation(s)
- Erika E Nishi
- Cardiovascular Division, Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | | | | | | |
Collapse
|
46
|
Acupuncture effect and central autonomic regulation. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:267959. [PMID: 23762116 PMCID: PMC3677642 DOI: 10.1155/2013/267959] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 04/03/2013] [Accepted: 04/03/2013] [Indexed: 02/07/2023]
Abstract
Acupuncture is a therapeutic technique and part of traditional Chinese medicine (TCM). Acupuncture has clinical efficacy on various autonomic nerve-related disorders, such as cardiovascular diseases, epilepsy, anxiety and nervousness, circadian rhythm disorders, polycystic ovary syndrome (PCOS) and subfertility. An increasing number of studies have demonstrated that acupuncture can control autonomic nerve system (ANS) functions including blood pressure, pupil size, skin conductance, skin temperature, muscle sympathetic nerve activities, heart rate and/or pulse rate, and heart rate variability. Emerging evidence indicates that acupuncture treatment not only activates distinct brain regions in different kinds of diseases caused by imbalance between the sympathetic and parasympathetic activities, but also modulates adaptive neurotransmitter in related brain regions to alleviate autonomic response. This review focused on the central mechanism of acupuncture in modulating various autonomic responses, which might provide neurobiological foundations for acupuncture effects.
Collapse
|
47
|
Littlejohn NK, Siel RB, Ketsawatsomkron P, Pelham CJ, Pearson NA, Hilzendeger AM, Buehrer BA, Weidemann BJ, Li H, Davis DR, Thompson AP, Liu X, Cassell MD, Sigmund CD, Grobe JL. Hypertension in mice with transgenic activation of the brain renin-angiotensin system is vasopressin dependent. Am J Physiol Regul Integr Comp Physiol 2013; 304:R818-28. [PMID: 23535460 DOI: 10.1152/ajpregu.00082.2013] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
An indispensable role for the brain renin-angiotensin system (RAS) has been documented in most experimental animal models of hypertension. To identify the specific efferent pathway activated by the brain RAS that mediates hypertension, we examined the hypothesis that elevated arginine vasopressin (AVP) release is necessary for hypertension in a double-transgenic model of brain-specific RAS hyperactivity (the "sRA" mouse model). sRA mice experience elevated brain RAS activity due to human angiotensinogen expression plus neuron-specific human renin expression. Total daily loss of the 4-kDa AVP prosegment (copeptin) into urine was grossly elevated (≥8-fold). Immunohistochemical staining for AVP was increased in the supraoptic nucleus of sRA mice (~2-fold), but no quantitative difference in the paraventricular nucleus was observed. Chronic subcutaneous infusion of a nonselective AVP receptor antagonist conivaptan (YM-087, Vaprisol, 22 ng/h) or the V(2)-selective antagonist tolvaptan (OPC-41061, 22 ng/h) resulted in normalization of the baseline (~15 mmHg) hypertension in sRA mice. Abdominal aortas and second-order mesenteric arteries displayed AVP-specific desensitization, with minor or no changes in responses to phenylephrine and endothelin-1. Mesenteric arteries exhibited substantial reductions in V(1A) receptor mRNA, but no significant changes in V(2) receptor expression in kidney were observed. Chronic tolvaptan infusion also normalized the (5 mmol/l) hyponatremia of sRA mice. Together, these data support a major role for vasopressin in the hypertension of mice with brain-specific hyperactivity of the RAS and suggest a primary role of V(2) receptors.
Collapse
Affiliation(s)
- Nicole K Littlejohn
- Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Kishi T, Hirooka Y. Oxidative stress in the brain causes hypertension via sympathoexcitation. Front Physiol 2012; 3:335. [PMID: 22934082 PMCID: PMC3429101 DOI: 10.3389/fphys.2012.00335] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 07/30/2012] [Indexed: 12/31/2022] Open
Abstract
Activation of the sympathetic nervous system (SNS) has an important role in the pathogenesis of hypertension, and is determined by the brain. Previous many studies have demonstrated that oxidative stress, mainly produced by angiotensin II type 1 (AT(1)) receptor and nicotinamide adenine dinucleotide phosphate (NAD (P) H) oxidase, in the autonomic brain regions was involved in the activation of the SNS of hypertension. In this concept, we have investigated the role of oxidative stress in the rostral ventrolateral medulla (RVLM), which is known as the cardiovascular center in the brainstem, in the activation of the SNS, and demonstrated that AT(1) receptor and NAD (P) H oxidase-induced oxidative stress in the RVLM causes sympathoexcitation in hypertensive rats. The mechanisms in which brain oxidative stress causes sympathoexcitation have been investigated, such as the interactions with nitric oxide (NO), effects on the signal transduction, or inflammations. Interestingly, the environmental factors of high salt intake and high calorie diet may also increase the oxidative stress in the brain, particularly in the RVLM, thereby activating the central sympathetic outflow and increasing the risk of hypertension. Furthermore, several orally administered AT(1) receptor blockers have been found to cause sympathoinhibition via reduction of oxidative stress through the inhibition of central AT(1) receptor. In conclusion, we must consider that AT(1) receptor and the related oxidative stress production in the brain cause the activation of SNS in hypertension, and that AT(1) receptor in the brain could be novel therapeutic target of the treatments for hypertension.
Collapse
Affiliation(s)
- Takuya Kishi
- Department of Advanced Therapeutics for Cardiovascular Diseases, Kyushu University Graduate School of Medical Sciences Fukuoka, Japan
| | | |
Collapse
|
49
|
Paterno JC, Bergamaschi CT, Campos RR, Higa EMS, Soares MF, Schor N, Freire AO, Teixeira VPC. Electroacupuncture and moxibustion decrease renal sympathetic nerve activity and retard progression of renal disease in rats. Kidney Blood Press Res 2012; 35:355-64. [PMID: 22473039 DOI: 10.1159/000336095] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 12/27/2011] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND/AIM Chronic kidney disease (CKD) is an increasing major public health problem worldwide. The sympathetic nervous system and nitric oxide play an important role in the pathogenesis of CKD. Traditional Chinese medicine has accumulated thousands of years of therapeutic experiences. Electroacupuncture (EA) and moxibustion (MO) are two such therapeutic strategies. The aim of this study was to investigate the renal and hemodynamic effects of EA-MO in an experimental model of a CKD. METHODS Male Wistar rats submitted to 5/6th nephrectomy (5/6 NX) were studied for 8 weeks. There were four groups: (1) control, normal rats; (2) NX, 5/6 NX only; (3) NX-AS, 5/6 NX and EA-MO session using sham points, and (4) NX-AM, 5/6 NX and EA-MO session using real acupoints. Biochemical and blood pressure studies, renal sympathetic nerve activity measurements, nitric oxide levels and the histopathological indices were assessed. RESULTS The EA- and MO-treated group presented significant improvement in all measured functional and histopathological parameters. CONCLUSION These findings suggest that EA-MO had beneficial effects on CKD. This effect was probably achieved by the modulation of the renal sympathetic nerve activity and nitric oxide levels, leading to decreased blood pressure, which is associated with less proteinuria.
Collapse
Affiliation(s)
- Josne C Paterno
- Nephrology Division, Department of Medicine, Federal University of São Paulo (UNIFESP), São Paulo, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Nitric oxide at the CVLM is involved in the attenuation of the reflex bradycardia in renovascular hypertensive rats. Nitric Oxide 2012; 26:118-25. [DOI: 10.1016/j.niox.2012.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 12/06/2011] [Accepted: 01/06/2012] [Indexed: 01/09/2023]
|